Back in 2018, I posted about the online vendors that I’ve used. Since that time, I have added another. Dave’s Rare Aquarium Fish out of San Antonio, TX is a vendor you should consider adding to your list. Besides the fact that owner Dave Schumacher is just a nice guy, I can vouch for his fish.
I did an interview with Dave back in 2019. Check it out to learn more about his business. He and I are working on a second interview now.